mongodb-query

问题 I have a json file returned from mongo db as follow: [ { "_id": { "$date": "2014-10-19T04:00:00.000Z" }, "value": 29 }, { "_id": { "$date": "2014-10-20T04:00:00.000Z" }, "value": 20 }, { "_id": { "$date": "2014-10-21T04:00:00.000Z" }, "value": 21 } ] Now I want to read the date in java in the following format: 2014/10/25 but when I use: System.out.println("DAte is : "+result.get("_id").toString() ); the result is : DAte is : Sun Oct 19 01:00:00 ADT 2014 Then only thing that comes to my mind

问题 I have a hashed based sharding enabled for a key "userId" in a mongodb collection. Is it possible to get all documents whose hashed values of "userId" are between, let's say, "abcd" and "cdef"? Thanks! 回答1: One way that I found is to use the following query: db.mycollection.find({ "$and": [ {_id: {"$gt": -5012941854059245285}}, {_id : {"$lt": -4712634714892678072}} ]}).hint({_id: "hashed"}) where the long numbers are hashed values of _id. It works for me, but is it the best way of doing so?

问题 I am trying to store some geojson points in mongo db.Here is the mongoose schema I have defined. new mongoose.Schema({ itemName:String, loc:{ type: [Number], index: '2dsphere'} }); Next I am trying to run a near operator to find out some points nearby.This is how I have defined the near query. Model.where('loc').near({ center: { type:"Point",coordinates: [10,10] }, maxDistance: 20 }).exec(function(err,data){ console.log(err); if (!err && data) { console.log("Success"); } else { console.log(

问题 This is my mongodb shell command: db.dais_employee.aggregate([ { "$redact": { "$cond": { "if": { "$gt": [ { "$subtract": [ "$modifiedon", "$createdon" ] }, 1000 * 60 * 60 * 24 ] }, "then": "$$KEEP", "else": "$$PRUNE" } } } ]) which works fine. I need to work this MongoDB command in java and I need help for using MongoDB Aggregation framework with java driver. When I am trying to run this command using java driver: AggregateIterable<Document> iterable = collection.aggregate(asList( new

问题 I don't quite understand to use $or or $and operators with MongoDB. Let's say I have following data: { "_id" : "0211dd50-6283-11e6-be4b-01259186ebdc", "customer_id" : 75832, "prod_display_id" : "8c890b9c-7824-11e5-9cf1-24519096eb0c", "record_ids" : [ ObjectId("1377ki5f8782b634fbf92b07b"), ObjectId("6283gf5f922b634fbf32b07a"), ObjectId("9913zd5f234b634fbf22b07c") ], "create_dt" : ISODate("2014-01-12T13:31:42.740Z") }, { "_id" : "3454ke24-9372-11e6-be4b-01259186ebdc", "customer_id" : 75832,

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 3 years ago . I want to handle nested category in Mongo and Meteor framework for several Ads. For example like this: Ads object have category field like this: MainCategory_1 > SubCategory_1.1 > SubCategory_1.1.1 > SubCategory_1.1.1.1 > { Ad_1 HERE } > SubCategory_1.2 > SubCategory_1.2.1 >

问题 public void SearchForDate(String date) { Information object = new Information(); List<Information> list = new ArrayList<Information>(); MongoCursor<Document> cursor = collection.find(eq("date", date)).iterator(); while (cursor.hasNext()) { System.out.println(cursor.next().toJson()); } } Hi, I want inserting the cursor.next().toJson() information on a new object of the information class, how I could do it? the cursor just return a String... public void BuscarPorPalabra(String date) {

问题 I am trying to do the following query in Mongo: SELECT * FROM events WHERE v1 - v2 > 20; where v1 and v2 are names of columns in the SQL DB. how can I translate it to Mongo Languague? 回答1: Assume you have these documents in your events : { "_id" : ObjectId("54cdfde528bb923955eff8b4"), "v1" : 35, "v2" : 10 } /* 1 */ { "_id" : ObjectId("54cdfde928bb923955eff8b5"), "v1" : 10, "v2" : 20 } You cant use a simple find() query. You should use aggregation: db.events.aggregate( [ { $project : { 'diff'

问题 This question already has answers here : Sum in nested document MongoDB (2 answers) Closed 4 years ago . db.logdata.findOne() { "_id" : ObjectId("552cfc949258ff1fa8686f1a"), "ldl_date" : "2015-04-09", "ldl_mmo_id" : 5, "ldl_master_info_id" : 11, "ldl_publication_info_id" : 41616, "detail" : [ { "ldl_id" : 54261629, "ldl_xml_info_id" : 37437691, "ldl_distribution_id" : 3289, "ldl_local_flag" : 1, "ldl_ftp_flag" : 0, "ldl_time" : "2015-04-09 06:36:46" } ] } I need to access the ldl_local_flag

问题 I take data from a search box and then insert into MongoDB as a document using the regular insert query. The data is stored in a collection for the word "cancer" in the following format with unique "_id". { "_id": { "$oid": "553862fa49aa20a608ee2b7b" }, "0": "c", "1": "a", "2": "n", "3": "c", "4": "e", "5": "r" } Each document has a single word stored in the same format as above. I have many documents as such. Now, I want to remove the duplicate documents from the collection. I am unable to